This invention relates to recoverable wraparound closures having longitudinal edge regions such as rails which can be brought together around a substrate, such as a cable, and having closure means for holding those edge regions together in abutting position. Such wraparound closures frequently have a flap which extends from one of the edge regions underneath the gap between the two abutting edge regions of the closure. These flaps are of various configurations to perform the function of assuring the seal of the gap between the abutting edge portions of the wraparound closure. Examples of such flaps are shown in the following commonly-assigned copending applications which are incorporated herein by reference. In U.S. Ser. No. 388,791, now U.S. Pat. No. 4,436,566, filed June 15, 1982, the flap underlying the gap between the edge regions of the wraparound closure includes means for forcing adhesive into the gap to assure proper seal. In U.S. Pat. No. 4,384,906 issued May 24, 1983 and copending application U.S. Ser. No. 415,670 filed Sept. 17, 1982, a flap is shown which is formed from the wraparound sheet itself. In copending Application U.K. Ser. No. 8,236,056 filed Dec. 17, 1982, the flap has a certain configuration to assure structural integrity and to avoid damage to the flap during the recovery of the wraparound closure. Another example of the flap extending from one edge of a wraparound closure is shown in U.S. Ser. No. 517,542 filed July 25, 1983.
In another form of closure, a flap is not used. Examples of such closures are those for pressurized splice cases which have internal rigid frame around which the wraparound closure is placed. The end portions of such wrap-arounds are either mechanically closed or recovered to seal the ends around the substrate. The seal between the edge portions which are abutted together to form the closure in these pressurized splice applications is accomplished by an independent sealing member which is attached to the rigid frame. An example of such configuration is shown in copending application U.S. Ser. No. 483,017 filed Apr. 7, 1983, and in U.S. Ser. No. 308,886 filed Oct. 5, 1981.
It is also common to use a liner in conjunction with recoverable wraparound closures to provide a base or a substrate without uneven surfaces or protrusions for the recoverable wraparound to shrink down against and form the required seal and environmental protection. The liners are designed to perform various functions, such as heat-shielding during recovery, and are placed on the cable or substrate, compressed to the appropriate size around the splice bundle, then secured in place usually with plastic tape. The wraparound is then placed around the substate and liner and recovered to engage the liner and the exposed portion of the substrate by shrinking down against the liner and the substrate. An example of such a liner is shown in copending application U.S. Ser. No. 401,177 filed July 23, 1982. The liners are also used in aid in re-entry of the closure, such as the liner configuration disclosed in copending application U.S. Ser. No. 341,407 filed Jan. 21, 1982.